How Human Activity is Triggering an Uplift in Earth’s Mantle: The ‘Quiet Chernobyl’ Phenomenon Explained

Central Asia’s Aral Sea, once one of the world’s largest lakes, is now experiencing a surprising twist. Recent research shows that the ground below is slowly rising, a phenomenon tied to past human actions that drastically changed the landscape.

In the 1960s, water from two major rivers was diverted for irrigation, leading to a significant drop in the Aral Sea’s water levels. This disaster is often referred to as the “quiet Chernobyl” because of its harmful impact on the environment and local communities. The lake split into two by 1986, and since then, it has lost an astonishing 1.1 billion tons of water—about the weight of 150 Great Pyramids of Giza.

Experts like Simon Lamb from Victoria University of Wellington explain that the loss of this massive water weight initially caused a slight rebound of the Earth’s crust. However, new findings reveal that the land is still rising decades later. The researchers used a method called interferometric synthetic aperture radar (InSAR) to measure these subtle changes, detecting a bulge extending 310 miles around the former lake.

From 2016 to 2020, they found this area rose about 0.3 inches annually. This ongoing uplift occurs because the Earth’s mantle, which consists of thick rock capable of moving, is gradually compensating for the lost water. It’s a natural process similar to what happens in Scandinavia, where mantle rocks shift to replace material lost due to melting ice from the last ice age.

As the Aral Sea shrinks, it has transformed into a dry desert littered with rusted ships that once sailed its waters. This stark image highlights the severe consequences of environmental mismanagement. By 2007, the sea had dwindled to the point that even the two lakes formed after the original split further fragmented, with one basin disappearing completely by 2020.

The drying up of the Aral Sea has led to increased desertification and drought in the region. In 2014, the situation was so dire that it was likened to a nuclear disaster in terms of its ecological and economic fallout. The local communities have suffered, facing job losses in fishing industries that once thrived.

This situation serves as a critical reminder of how interconnected human actions are with natural systems. The science of InSAR not only reveals changes on land but also illustrates the long-lasting impact of environmental decisions. As we push for a more sustainable future, it’s essential to learn from these lessons and understand the long-term effects of our interactions with nature.

For those interested in exploring the details of this study, you can find it published in the journal Nature Geoscience.



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